A typical liquid crystal display (LCD) is capable of displaying a clear and sharp image through thousands or even millions of pixels that make up the complete image. The liquid crystal display has thus been applied to various electronic equipment in which messages or pictures need to be displayed, such as mobile phones and notebook computers. A liquid crystal panel is a major component of the LCD, and generally includes two substrates and liquid crystal filled in a space defined between the two substrates.
Methods of filling the liquid crystal in the space include an injection method and a one drop fill (ODF) method. The injection method includes the following steps: coating sealant along an outer periphery of one of the substrates, and defining one or more small gaps in the sealant; placing the other substrate onto the substrate having the sealant, and curing the sealant; immerging the assembly into liquid crystal in a vacuum environment so that the gaps in the sealant receive liquid crystal; and diminishing the vacuum environment such that the liquid crystal is pushed into the space between the two substrates through the gaps by atmospheric pressure. The ODF method includes the following steps: coating sealant along an outer periphery of one of the substrates, thereby defining a rectangular space; dropping liquid crystal on the substrate in the space; placing the other substrate onto the substrate having the sealant and the liquid crystal in a vacuum environment; and curing the sealant.
Referring to FIG. 9, this is a flowchart summarizing a typical method for fabricating a liquid crystal panel. The method includes the following steps.
In step S1, referring also to FIG. 10, a first substrate 110 is provided.
In step S2, a plurality of color resin layers 111 and a black matrix 17 spacing the color resin layers 111 are formed on the first substrate 110. The color resin layers 111 include red resin layers 11, green resin layers 12, and blue resin layers 13.
In step S3, a plurality of photo spacer 14 are formed on the black matrix 17. The photo spacers 14 have a same height. Each photo spacer 14 is disposed between two color resin layers 111 having a same color.
In step S4, a second substrate (not shown) is provided.
In step S5, sealant is coated along an outer periphery of the second substrate, whereby the second substrate and the sealant cooperatively define a space.
In step S6, liquid crystal is dropped on the second substrate in the space.
In step S7, the first substrate 110 having the color resin layers 111, the black matrix 17 and the photo spacers 14 is placed onto the second substrate and is pressed in a vacuum environment.
In step S8, the sealant is cured.
Because the photo spacers 14 have a same height, a total contact area between the photo spacers 14 and the second substrate is large. Therefore when the first substrate 110 is pressed, compression of the photo spacers 14 is limited and the diminution in height of the photo spacers 14 is minimal. As a result, it is difficult for the liquid crystal to fill the entire space between the two substrates. This means dropping of the liquid crystal must be precisely controlled within a narrow tolerance range. That is, the method for fabricating the liquid crystal panel is problematic, and yields can be low.
What is needed, therefore, is a method for fabricating a liquid crystal panel that can overcome the above-described problems.